LANSING, MI - The Libertarian Party of Michigan said Monday it will sue the secretary of state to put its candidate on the presidential ballot, continuing a fight that could have bigger implications if the race between President Barack Obama and Mitt Romney is razor-tight.

The Libertarians were warned by the state to not nominate former New Mexico Gov. Gary Johnson for president because his name was on Michigan's GOP presidential primary ballot in February. Under the state's so-called "sore loser law," a candidate who loses a primary cannot be nominated by another party to run in the general election.

The state Libertarian Party decided to nominate Johnson anyway at its June 2 convention.

Party spokesman Michael Moon said Johnson dropped out of the race for the GOP nomination in December and tried to remove his name from Michigan's primary ballot only to have the state Bureau of Elections tell him he filed his withdrawal affidavit three minutes too late.

"We're not playing their games basically," he said Monday while complaining about not getting calls returned from elections officials. A lawsuit is being prepared, he said.

Fred Woodhams, a spokesman for Republican Secretary of State Ruth Johnson, said the law is clear.

"He did try to remove himself from the (primary) ballot but did not send in the affidavit stating he was not a candidate in time. So he was left on the ballot," he said. "We're following the law here."

In 2008, Libertarian presidential candidate Bob Barr received under 24,000 of about 5 million votes cast in Michigan, or less than one-half of 1 percent. It is a tiny amount that had no bearing on Barack Obama's comfortable win over John McCain - but might if Michigan has a razor-thin race in 2012 like Florida had in 2000, which was decided by 543 votes.

Voters who agree with the Libertarian Party's positions could vote Republican if their choice is only between a Republican and a Democrat. The spoiler effect of the Libertarian Party on GOP candidates and the Green Party on Democratic candidates is disputed by third parties, who say voters simply deserve more choices.

As a backup plan, the Libertarian Party said it voted to put a Gary E. Johnson of Austin, Texas, on the Michigan presidential ballot if former Gov. Gary Johnson is barred, pending the results of legal action. It was not immediately clear if that maneuver is allowable.

Moon said that in 1980, Democratic Secretary of State Richard Austin did not apply the sore-loser law to John Anderson, who ran in the GOP presidential primary and was allowed to run in November as a candidate of the Anderson Coalition Party.

"The Libertarian Party is known as the Party of Principle," said Denee Rockman-Moon, chairwoman of the Libertarian Party of Michigan. "We are starting to wonder what happened to Secretary of State Ruth Johnson's principles."

Woodhams, however, said that in 1980 there was no mechanism for an independent candidate to get on the ballot. Johnson, he said, could submit at least 30,000 valid signatures by July 19 to run as an independent in Michigan.